Leads to the Heart – An Extraction Evolution

Over the past two years, the FDA and device manufacturers have placed an increased level of importance on tracking device performance in an effort to ensure complete patient safety.

Pacing leads, which connect pacemakers and defibrillators to the heart, have received particularly close attention from regulators and the media. These leads are intended to deliver an electric shock, when necessary, to stabilize a dangerously erratic heartbeat and as such are a major component to the set-up of a pacemakerdefine or defibrillatordefine.

As the number of cardiacdefine lead implants increases each year so too does the need to extract a portion of the lead wires. In the U.S., more than 20,000 to 25,000 leads are extracted annually. Lead wires that become infected, damaged or blocked must be removed to avoid serious complications.

Additionally, current lead wire extraction practices can be extremely painful and intrusive for patients, many of whom are elderly and frail. Fortunately, the past decade has brought forth an increase in sharp, skilled lead extraction specialists who are pioneering less-invasive procedures for lead extraction.

Extraction Technology and Techniques

Traditional Methods

In the years following the introduction of chronically implanted transvenous pacing leads, a variety of methods for lead removal were trialed, the simplest being traction, often called the “drag through” technique. For patients with significant fibrous overgrowth, more aggressive methods had to be developed, including traction applied by weights and elastic bands among other methods.

Nonetheless, complications and difficulties encountered when using traction for lead removal led some investigators to surgical approaches, whereby the heart and great veins were exposed via sternotomy or thoracotomy allowing extraction of a lead via an incision in the atrium or ventricledefine.

In greatly experienced hands, these techniques produced high success rates, but required highly specialized skills gained through years of training. In addition, these techniques were associated with morbidity and the heavy economic impact of open surgery.

The desire for safe and more economically viable extraction techniques led to the development of intravascular counter-pressure and counter-traction – using telescopic sheaths made of polymer and /or steel material, which would slide over the lead body.

This technique removes the fibrotic tissue that develops over time and entraps the implanted lead in the veins. As the sheaths are advanced over leads to tear and peel away the encapsulating tissue they achieve a transvenous removal of leads with minimised risk to the patient compared with previous methods.

Today’s Alternative

The procedure of lead removal has matured into a definable, teachable art with its own specific tools and techniques. Today’s technology offers two main technology options for surgeons performing extractions – laser and mechanical.

Laser extraction requires a 600 pound stand alone unit to interface and power an SLS laser sheath, with each sheath requiring complex calibration before each use. Heavy machinery like this requires support by way of annual maintenance and biomedical inspection as well as the requirement to employ an on-site laser officer. Put simply, it’s bulky and costly both in terms of operation, training and maintenance.

The other option is to use a mechanical approach. This offers benefits in that it requires less surgical finesse and is more intuitive to use than laser powered systems. It is also designed to negotiate chronic, heavily fibrosed and calcified lesions without requiring the ‘brute strength’ of traction.

An enhanced mechanical extraction approach doesn’t have the forward depth of cut like laser extraction sheaths. With this in mind, mechanical extraction historically has had a lower adverse event rate than that experienced using powered sheaths.

Today’s mechanical lead extraction technology has been designed to be as intuitive as possible for the surgeon specialist during a procedure. Lead extraction, which goes a long way in addressing device-related complications, has progressed, particularly as clinicians are more aware of the risks and complications associated with some of the techniques previously used. Mechanical techniques allow for greater success rates, thus making the patient’s journey also a much safer and enjoyable one.

While extraction of chronically implanted leads has been difficult in the past, this seems to have been addressed with mechanical techniques, which have been proven to remove the scar tissue along the veindefine that is often the primary reason for partial or failed removal of a lead.

An Exciting Evolution

Lead extraction device manufacturers have a responsibility to provide the best, most versatile devices that provide safe, timely and effective treatment for the patient, and are easy-to-use devices for surgeons.

Additionally, the need to reduce the financial burden of acquiring the best possible technology on health organizations needs to be reduced. It’s exciting to see the benefits that the lead extraction evolution will deliver to health providers, doctors and patients.

Barry Norlander is Global Marketing Manager of Vasculardefine Strategic Business Unit for Cook Medical, a world leader in lead extraction devices, techniques and technology.